Chen Fen, Li Juan, Sugiyama Hiromu, Zhou Dong-Hui, Song Hui-Qun, Zhao Guang-Hui, Zhu Xing-Quan
State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences , Lanzhou, Gansu Province , PR China .
Mitochondrial DNA. 2015 Feb;26(1):35-40. doi: 10.3109/19401736.2013.814110. Epub 2013 Jul 31.
The present study examined sequence variability in the mitochondrial (mt) protein-coding genes cytochrome b (cytb), NADH dehydrogenase subunits 2 and 6 (nad2 and nad6) among 24 isolates of Schistosoma japonicum from different endemic regions in the Philippines, Japan and China. The complete cytb, nad2 and nad6 genes were amplified and sequenced separately from individual schistosome. Sequence variations for isolates from the Philippines were 0-0.5% for cytb, 0-0.6% for nad2, and 0-0.9% for nad6. Variation was 0-0.5%, 0.1-0.8%, 0-0.7% for corresponding genes for schistosome samples from mainland China. For worms in Japan, genetic variations were 0-0.2%, 0.1-0.2% and 0 for the three genes, respectively. Sequence variations were 0-1.0%, 0-1.8% and 0-1.1% for cytb, nad2 and nad6, respectively, among schistosome isolates from different geographical strains in the Philippines, Japan and China. Of the three countries, lowest sequence variations were found between isolates from mainland China and the Philippines and highest were detected between Japan and the Philippines in three mtDNA genes. Phylogenetic analyses based on the combined sequences of cytb, nad2 and nad6 revealed that all isolates in the Philippines clustered together sistered to samples from Yunnan and Zhejiang provinces in China, while isolates from Yamanashi in Japan were in a solitary clade. These results demonstrated the usefulness of the combined three mtDNA sequences for studying genetic diversity and population structure among S. japonicum isolates from the Philippines, China and Japan.
本研究检测了来自菲律宾、日本和中国不同流行区的24株日本血吸虫线粒体（mt）蛋白编码基因细胞色素b（cytb）、NADH脱氢酶亚基2和6（nad2和nad6）的序列变异性。分别从单个血吸虫中扩增并测序完整的cytb、nad2和nad6基因。菲律宾分离株的cytb序列变异为0-0.5%，nad2为0-0.6%，nad6为0-0.9%。中国大陆血吸虫样本相应基因的变异分别为0-0.5%、0.1-0.8%、0-0.7%。对于日本的虫体，这三个基因的遗传变异分别为0-0.2%、0.1-0.2%和0。菲律宾、日本和中国不同地理株的血吸虫分离株中，cytb、nad2和nad6的序列变异分别为0-1.0%、0-1.8%和0-1.1%。在这三个国家中，中国大陆和菲律宾分离株之间的序列变异最低，而日本和菲律宾之间在三个线粒体DNA基因中检测到的变异最高。基于cytb、nad2和nad6联合序列进行的系统发育分析表明，菲律宾的所有分离株聚在一起，与中国云南和浙江省的样本形成姐妹群，而日本山梨县的分离株则处于单独一个分支中。这些结果证明了联合三个线粒体DNA序列在研究菲律宾、中国和日本日本血吸虫分离株的遗传多样性和种群结构方面的实用性。
